SIMULTECH 2018 Abstracts


Area 1 - Simulation Tools and Platforms

Full Papers
Paper Nr: 8
Title:

Atomistic Modelling and Simulation of Transmission Electron Microscopy Images: Application to Intrinsic Defects of Graphene

Authors:

Cyril Guedj, Léonard Jaillet, François Rousse and Stéphane Redon

Abstract: The characterization of advanced materials and devices in the nanometer range requires complex tools, and the data analysis at the atomic level is required to understand the precise links between structure and properties. This paper demonstrates that the atomic-scale modelling of graphene-based defects may be performed efficiently for various structural arrangements using the Brenner module of the SAMSON software platform. The signatures of all kinds of defects are computed in terms of energy and scanning transmission electron microscopy simulated images. The results are in good agreement with all theoretical and experimental data available. This original methodology is an excellent compromise between the speed and the precision required by the semiconductor industry and opens the possibility of realistic in-silico research conjugated to experimental nanocharacterisation of these promising materials.

Paper Nr: 27
Title:

New Approach for Mobility Management in Openflow/Software-Defined Networks

Authors:

N. Omheni, F. Zarai, B. Sadoun and M. S. Obaidat

Abstract: The Software-Defined Networking (SDN) paradigm predicts that the evolution of cellular and wireless networks will bring a considerable increase of two factors, the densification of the Radio Access Network (RAN) part and the progressive demand for traffic. This rapid evolution has led to the emergence of extremely complicated systems, where a large number of logic modules must interact to lead to the desired behavior and the desired quality of service. The key advantage of SDNs is the simplicity of networking and the deployment of new mechanisms and applications. Furthermore, the programmable aspect on the traffic and devices in SDNs makes them more efficient and flexible than traditional networks. In this context, Distributed Mobility Management (DMM) has been recently presented as a new trend to solve the issues of the today’s mobility management protocols. In this paper, we propose a partially distributed Mobility Management for OpenFlow/SDN networks. According to simulation results, our approach guarantees a significant reduction of the number of handover and the signaling cost.

Paper Nr: 40
Title:

Use of the Sinusoidal Predictor Method within a Fully Separated Modeler/Solver Framework for Fast and Flexible EMT Simulations

Authors:

Pierre-Marie Gibert, Romain Losseau, Adrien Guironnet, Patrick Panciatici, Damien Tromeur-Dervout and Jocelyne Erhel

Abstract: In order to help the introduction of renewable energy sources into the power system, transmission system operators need extremely reliable simulation tools. In most of the existing simulation tools, heuristics used to accelerate the simulations combine the modeling and solving aspects. Such kinds of approaches lead to results whose validity can be questioned. In contrary, our framework aims at avoiding such heuristics by completely separating the modeler and the solver. However, such an approach is difficult as the computational cost may be significantly higher. In addition, as we simulate the full-waveform of AC power systems, the time step size used by classical methods for integrating the arising systems of DAE is limited by the frequency of some electrical components. This is why we developed an efficient solver based on the reference solver SUNDIALS IDA which takes into account the guessed sinusoidal behavior of the solution oscillating parts in order to lower the number of iterations for performing a simulation. Our first results seem to indicate that the proposed solver enables to use much larger time steps than a standard integration scheme, while preserving a very high flexibility of modeling.

Paper Nr: 41
Title:

Harnessing Web 3.0 and R to Mitigate Simulation Validation Restrictions

Authors:

Bill Roungas, Sebastiaan Meijer and Alexander Verbraeck

Abstract: The complexity of modern systems has made the use of simulations paramount, in order to test different scenarios in an affordable, ethical, and risk-free way. As such, simulations need to be validated, ensuring that the obtained results are meaningful. But validation apart from the computational difficulties, bears several other problems. The constant need for validation due to updates on the simulation software, the dependence on the validation experts to be always available for the new iterations and for presenting any new insights are just some of these problems. This paper proposes a framework, and applies it to two case studies, which is based on Web 3.0 technologies and the R statistical language as a mean to mitigate such problems.

Paper Nr: 63
Title:

Particle based Waterfall Simulation with Spray Cloud Emerging from Basin

Authors:

Nobuhiko Mukai, Yuto Hizono and Youngha Chang

Abstract: One of the most challenging issues is to simulate and visualize physical phenomena such as thunder, aurora, avalanche and so forth. Among them, simulation of liquid behavior is difficult but most familiar to us. Then, there are many researches related to water; however, there are not so many studies on waterfall. Some researchers visualized waterfall behavior, which, however, was not based on physical simulations. Other papers on physics based simulations demonstrated part of waterfall instead of the whole behavior. Then, we have tried to visualize the whole behavior of waterfall with a physics based particle method. In order to simulate the whole behavior of waterfall, huge amount of particles are needed so that our model divides the whole of waterfall into three parts: water stream, splashing spray, and spray cloud. In the previous works, we have been able to visualize the whole behavior of waterfall, where water stream was translated to splashing spray that was also changed into spray cloud. Then, the previous method had splashing spray and spray cloud emerging from water stream, while real waterfalls have spray cloud that appears from the basin instead of water stream. Therefore, this paper proposes a model to generate spray cloud emerging from the basin instead of water stream.

Paper Nr: 76
Title:

Supporting 5G Wireless Networks Through IEEE802.11ac Standard With New Massive MIMO Antenna System Module Design in Omnet++ Simulator

Authors:

Vincenzo Inzillo, Floriano De Rango and Alfonso Ariza Quintana

Abstract: The advances accomplished in the modern wireless network design are requiring increasingly more efficient high-performing antenna devices in order to satisfy the requirements provided for the 5G next generation systems; although a considerable number of theoretical proposals already exist in this field the most common used network simulators do not offer a support for the latest wireless network standards such as the IEEE802.11ac and, at the same time, they do not afford the possibility to utilise the latest up-to-date high performance massive MIMO (Multiple Inputs Multiple Output) antenna systems. In view of this, we propose to extend the basic feature offered by the Omnet++ network simulator with the aim of actualizing the current simulation instruments for enabling the emulation of 5G wireless network scenarios.

Short Papers
Paper Nr: 19
Title:

Effect of Price Dynamics in the Design of Eco-Industrial Parks: An Agent-based Modelling Approach

Authors:

Ganiyu O. Ajisegiri and Frans L. Muller

Abstract: Even though eco-industrial parks (EIP) models have proved to transform industrial areas by strengthen the emergence of sustainable EIP, there is a noticeable lack of research addressing the economic returns of the participating companies in the network which fluctuates according to prices offered for the resource exchange over time. In this paper, we develop an agent-based model sometimes refer to as bottom-up approach for the design of EIP in which price fluctuation and demand variability are emergent properties of the interaction among the agents. Agent-based modelling (ABM) is a computational methodology used in social science, biology, and other fields. It represents autonomous entities, each with dynamic behaviour. The agents within the eco-industrial park are the factories, market buyers and market sellers. The computational development was performed in Réseau.py, which was built in Python (a programmable modelling environment) from scratch. Based on the autonomy of each of the agents and their individual objectives, simulations were carried out on a bio-energy based EIP (BBEIP) system in order to study the influence of price fluctuation between the agents. The results show that variability in price is a factor for establishing symbiotic relationship among the symbiotic agents in the EIP.

Paper Nr: 21
Title:

The Impact of Psychological and Demographic Parameters on Simulator Sickness

Authors:

Stephan Schweig, Magnus Liebherr, Dieter Schramm, Matthias Brand and Niko Maas

Abstract: In a world, which is characterized by technical progress, virtual environment technologies become increasingly relevant. In this context, simulators are used as a cost and time efficient methods for investigating innovative developments, training effects, but also the influence of individual attributes such as the process of aging. Although the simulator technologies have been greatly developed in recent years, they are not able to perfectly replicate the real world, which causes problems of system adaptation and simulator sickness. In the paper at hand, we will focus both, the time of adaptation to the virtual environment and the phenomenon of simulator sickness under the aspect of mental abilities and the process of aging, based on a driving simulator study with 414 participants.

Paper Nr: 25
Title:

A Simulation-driven Approach in Risk-aware Business Process Management: A Case Study in Healthcare

Authors:

Ilaria Angela Amantea, Antonio Di Leva and Emilio Sulis

Abstract: Risk management in business process is a key factor of success for organization as risks are part of every business activity. Errors may bring to increased costs, loss of quality as well as time delays, which in healthcare can bring to serious damages. This paper proposes a methodological framework to investigate risks in organizations by adopting a Business Process Management perspective that includes modeling and simulation of business processes. We applied our methodology to processes in the Blood Bank department of a large hospital. Our results show that a simulation-driven approach is an effective way to intercept and estimate real risks and to provide a decision support to guide the of department’s managers.

Paper Nr: 43
Title:

Spatially Explicit Coupled Map Lattice Simulation of Malaria Transmission in the Brazilian Amazon

Authors:

Anthony E. Kiszewski, Marcia Castro and Sarah McGough

Abstract: End stage malaria elimination efforts will require interventions against transmission that is sparse, cryptic and spotty, situations suited for explicitly spatial simulation. A simulation of mosquito population dynamics and Plasmodium vivax malaria transmission in the Brazilian Amazon is described combining techniques of cellular automata and coupled map lattices. Within a 200x200 grid, 64 dispersed communities of 50 households each are represented with larval breeding sites following a random Gaussian distribution. Discrete representation of individual humans allows examination of the effect of circulation and migration. Continuous representation of mosquito abundance allows for more realistic scaling over space. Simulations (n=100) reach equilibrium within 200 daily time steps. Adult mosquito populations range between 230-241,000 individuals. An average parous rate of 56.5% for stable mosquito populations is consistent with values reported in local field studies of the primary vector, Anopheles darlingi. Equilibrium prevalence of P. vivax infections averages 3% (1.8-3.9%) and is highly sensitive to treatment seeking behaviour of asymptomatics. This simulation provides a stable platform that may be useful for investigating the role of human migration and asymptomatic malaria in perpetuating transmission cycles in this region and interventions supporting malaria elimination efforts.

Paper Nr: 45
Title:

An Overview of the Quartz Modelling and Simulation Framework

Authors:

Romain Franceschini, Paul-Antoine Bisgambiglia, Paul Bisgambiglia and David R. C. Hill

Abstract: Quartz is a modelling and simulation framework enabling the development and the execution of models based on the Parallel Discrete Event System Specification (PDEVS) formalism. In this paper we give an overview of the tool by giving details on its design and features. An experimental comparison shows that Quartz yields performances comparable to what is observed with aDEVS, one of the most efficient tool implemented with a compiled language. We present our efforts to provide dedicated expressions and verification facilities to the modeler and give examples of application domains that motivated this software. Namely, agent-based modeling through the Dynamic Parallel Discrete Event Multi-Agent (DPDEMAS) specification and multicomponent modeling with the multiPDEVS formalism.

Paper Nr: 46
Title:

Modelling Urban Logistics Business Ecosystems - An Agent-based Model Proposal

Authors:

Giovanni Zenezini and Alberto De Marco

Abstract: Urban Logistics (UL) faces several issues arising from e-commerce and population growth, and it is undergoing a series of technological and systemic innovations. However, most of these innovations fails to scale up, and high is the need to grasp the overall operational and economic aspects that drive UL stakeholders to accept such innovations. To this end, proper modelling and assessment methodologies need to take into account these aspects and the heterogeneity of objectives and decision-making of stakeholders. This paper aims at filling this gap by proposing an agent-based model based on an existing theoretical framework depicting UL systems from a business model perspective. A computational experiment is presented to retrieve more insights into the topic.

Paper Nr: 53
Title:

Application of Hybrid Petri Nets for a Drawing Blood Flow from Fingertip

Authors:

Shigenori Togashi, Kei Takenaka, Kenko Uchida, Takashi Irie, Taku Sakazume and Ryo Miyake

Abstract: Our objective of this study are to make a fluid dynamical model and to conduct the flow simulation for obtaining a large amount of drawing blood from a fingertip. The processes of drawing blood are hybrid systems including both the continuity system of blood flow and the discrete systems of cuff pressing and puncture. Therefore, we made the modelling of the fingertip drwaing blood process from the analogy of fluid daynamic tank and pipe systems control using hybrid Petri nets. Using the hybrid Petri nets simulation with cuff pressing and puncture modeled as discrete and blood flow modeled as continuity, we confirmed that the simulation results were agreement with the experimental drawing blood data.

Paper Nr: 55
Title:

Strategy for Reduction of the Negative Effects of Circumferential Flow Irregularity in Axial Compressor

Authors:

Aleksandr Ermakov, Grigorii Popov, Daria Kolmakova and Vasilii Zubanov

Abstract: Gas flow nonuniformity is one of the main sources of rotor blade vibrations in the gas turbine engines. Often, the source of the flow circumferential nonuniformity are the annular frames, located in the flow passage of the engine. This leads to the increased dynamic stresses in rotor blades and consequently to the blade destruction. The goal of the research was to find an acceptable method of reducing the level of gas flow nonuniformity. Thus, this study gives the ideas about methods of improving the flow structure in gas turbine engine. It allows the selection of the most suitable method for reducing gas flow nonuniformity.

Paper Nr: 67
Title:

The Use of Modelling within Prognostic Health Management Systems for a Fowler Flap System

Authors:

Graham Hardwick and Isabella Panella

Abstract: The aviation industry has been utilising prognostic health management (PHM) to improve scheduled maintenance, reduce expensive aircraft on ground events (AOG) and improve active safety. PHM systems utilise legacy and real time aircraft data in conjunction with simulation models to forecast the remaining useful life (RUL) of components and systems which allow maintenance decisions to be managed. This work presents an industry based approach to PHM for one of the aircraft line replacement units (LRUs), specifically, the power drive unit (PDU) within a “generic” commercial aircraft secondary flight control system. The modelling infrastructure and its importance as a building block for the construction of a prognostic health management framework are highlighted. Example failure modes of a PDU are provided and potential benefits of PHM to mitigate these failure modes are examined. Finally simulation results from a physical model of the system in Simulink have been generated.

Paper Nr: 78
Title:

Dockemu: Extension of a Scalable Network Simulation Framework based on Docker and NS3 to Cover IoT Scenarios

Authors:

Antón Román Portabales and Martín López Nores

Abstract: The purpose of this project was to extend an existing open-source simulation framework called Dockemu in order to make it suitable to perform IoT simulations. The work covered some improvements with goes from the support of more network technologies to the use of setup and deployment tools used by modern devops professionals. The paper explains the architecture, the newly-added features and the specific advantages it offers for research works in IoT network simulations.

Posters
Paper Nr: 16
Title:

Modelling of Quantum Key Distribution Protocols in Communicating Quantum Processes Language with Verification and Analysis in PRISM

Authors:

Satya Kuppam

Abstract: Proof of security of cryptography protocols theoretically establishes the strength of a protocol and the constraints under which it can perform, it does not take into account the overall design of the protocol. In the past model checking has been successfully applied to classical cryptography protocols to weed out design flaws which would have otherwise gone unnoticed. Quantum key distribution protocols differ from their classical counterparts, in their ability to detect the presence of an eavesdropper while exchanging the key. Although unconditional security has been proven for both BB84(Mayers, 2002) and B92(Quan and Chaojing, 2002) key distribution protocols, in this paper we show that identifying an eavesdropper’s presence is constrained on the number of qubits exchanged. We first model the protocols in Communicating Quantum Processes (CQP)(Gay and Nagarajan, 2005)(Davidson, 2012) and then explain the mechanism by which we have translated this into a PRISM model and how we analysed the protocols’ capabilities. We mainly focus on the protocols’ ability to detect an active eavesdropper and the extent to which an eavesdropper can retrieve the shared key without being detected by either party. We then conclude by comparing the performance of the protocols.

Paper Nr: 35
Title:

Membrane Layer Method to Separate Simulation and Visualization for Large-scale In-situ Visualizations

Authors:

Akira Kageyama, Naohisa Sakamoto and Kohei Yamamoto

Abstract: With the progress of simulation technology, the demand for the in-situ visualization in high-performance computing is increasing. We propose a multiple-program, multiple-data (MPMD) approach to the in-situ visualization to realize interactive in-situ visualizations. We separate processor nodes in a massively parallel computer system into two parts; one devoted only to the simulation and the other devoted only to the visualization. Both the simulation and visualization programs are parallelized by MPI (Message Passing Interface). The number of MPI processes for the visualization is the same or larger than that for the simulation. The multiple camera method that we proposed in our previous study enables interactive analysis of the visualization movies thus generated. The simulation and visualization programs are separated by a layer mimicking a semipermeable membrane. It is semipermeable because information runs in one-way from the simulation to the visualization through the layer, and the layer prevents the simulation program from being affected by visualization program’s possible delay. The membrane is implemented as two independent MPI programs which correspond to the front and back faces of it. The four MPI programs (the simulation, visualization, and membrane faces) are executed at once based on an MPMD framework.

Paper Nr: 71
Title:

Steps Towards a Balance between Adequacy and Time Optimization in Agent-based Simulations - A Practical Application of the Temporality Model Time Scheduling Approach

Authors:

Tahina Ralitera, Nathan Aky, Denis Payet and Rémy Courdier

Abstract: Simulation models are often used as decision support tools. They intend to imitate real world complex phenomena or processes. For this purpose, simulation platforms has the simulated models evolve by advancing a virtual time. Thus, users could benefit from shorter, but relevant simulations. The simulated time is managed by the scheduler and how this is done could significantly impact on the performance of the simulation platform. However, conventional time scheduling approaches are still limited in some situations. The temporality model approach was proposed as an interesting solution. It addresses a number of criteria that the classical time scheduling approaches do not fulfil. In this paper, we first describe the fundamental of the temporality model approach. Then, we implement it in a simulation model called the SKUADCityModel. Finally, we show the performance advantages of this type of approach.

Paper Nr: 75
Title:

Comparison of Linear State Signal Shaping Model Predictive Control with Classical Concepts for Active Power Filter Design

Authors:

Kathrin Weihe, Carlos Cateriano Yáñez, Georg Pangalos and Gerwald Lichtenberg

Abstract: Many power networks are currently under major change processes due to the necessary integration of renewable energy sources. This brings the need to include Active Power Filter (APF) as well as controlling them in an adequate way. New control concepts like Linear State Signal Shaping Model Predictive Control (LSSS MPC) are specialized for these tasks and complex compared to classical concepts. Simulation studies show the advantages of LSSS MPC in performance, robustness and Total Harmonic Distortion (THD) compensation.

Paper Nr: 79
Title:

Unity-based Simulation Scenarios to Study Driving Performance

Authors:

David González-Ortega, Francisco J. Díaz-Pernas, Mario Martínez-Zarzuela and Míriam Antón-Rodríguez

Abstract: In this paper, we present two 3D driving simulation scenarios and a vehicle model developed to analyze driving efficiency and safety. The scenarios include different roads, traffic, and events so that drivers can acquire driving competences and their performance can be tested. They were developed with Unity game engine, which allows to create 2D and 3D games and applications and to export them to many different platforms. The first scenario is urban with varied roads, crossroads controlled by traffic lights, and roundabouts. The second scenario is interurban with different road sections connected by roundabouts. The vehicle engine has been modeled setting the dependency between engine torque and rpm and the dependency of each gear and speed on fuel consumption. Automatic or manual gear shifting can be selected. During a simulation, the speed, rpm, gear, consumption, and traffic offences are showed in real time and stored in files for further processing. Seven people drove in the scenarios and their stored data enabled us to analyze differences in driving performance between them. The simulator was ranked positively by all the participants regarding ease of interaction, similarity to real driving, and usefulness for driving learning.

Paper Nr: 81
Title:

Do We Need a New Architecture for Simulating Power Systems?

Authors:

Gary Howorth and Ivana Kockar

Abstract: The delivery of electric power and organisation of electric power systems is an incredibly complex system, which will become ever more complex with an increased penetration of Distributed Energy Resources (DER), including electric vehicles and renewables. Optimization of such a system using conventional techniques is difficult and fraught with a myriad of issues, so simulation provides a more holistic approach to understanding the evolving issues. We argue that although power simulation frameworks exist they may be inadequate for simulating a more complex and evolving smart power grid infrastructure. A brief overview of research on existing systems is provided and this paper argues for the development of a distributed multi-scale, multi layered hybrid ABM/MAS system.

Paper Nr: 82
Title:

A Vehicular Traffic Simulator Model for Evaluating Electrical Vehicle Performances in a Configurable Mobility Scenario

Authors:

Pierfrancesco Raimondo, Amilcare Francesco Santamaria, Floriano De Rango and Antonio Bosco

Abstract: Nowadays Electrical Mobility (EM) is one of the most interesting topics in vehicular environment. With the increasing adoption of EV an appropriate management of hybrid traffic could be a key factor to drastically reduce environmental pollution and to enhance road safety. EVs were slowly becoming a reality in everyday life. A novel mobility model which takes into account their characteristics become necessary for describing the key factors that influence EM and its performances. Moreover, it is important to build a real world close scenario by using a novel ad-hoc simulator that implements modules which are able to capture EV behaviors. Therefore, remarkable contributions to the mobility model introduced in the simulator are: a slope factor that influence users’ speed and behavior as well as vehicle consumption, a Kinetic Energy Recovery System (KERS) emulation for EV to better simulate vehicles’ battery life and integrated module for communication issues which will be able to allow Vehicular Ad-Hoc Network (VANET) protocol integration. In this way, a deep analysis on different vehicles distribution ratio has been done as well as their impact on the overall scenario. Results are shown in the dedicated section.

Area 2 - Formal Methods

Full Papers
Paper Nr: 17
Title:

Iterative Construction of Complete Lyapunov Functions

Authors:

Carlos Argáez, Peter Giesl and Sigurdur Hafstein

Abstract: Dynamical systems describe the evolution of quantities governed by differential equations. Hence, they represent a very powerful prediction tool in many disciplines such as physics and engineering, chemistry and biology and even in economics, among others. Their importance relies on their capability of predicting, as a function of time, future states of the corresponding system under consideration by means of the current, known state. Many difficulties arise when trying to solve such systems. Complete Lyapunov functions allow for the systematic study of complicated dynamical systems. In this paper, we present a new iterative algorithm that avoids obtaining trivial solutions when constructing complete Lyapunov functions. This algorithm is based on mesh-free numerical approximation and analyzes the failure of convergence in certain areas to determine the chain-recurrent set.

Paper Nr: 28
Title:

Extension of the Model-based Pre-step Stabilization Method for Non-iterative Co-simulation - Including Direct-feedthrough

Authors:

Simon Genser and Martin Benedikt

Abstract: For integration of subsystems co-simulation tools and master algorithms have to cope with the problem of restricted access to subsystem information. Especially for efficient handling of inherent properties like stiffness and direct feedthrough of industrial co-simulations additional subsystem information is mandatory. As provision of dedicated partial derivatives, especially regarding subsystem states, is complex and computationally expensive, recently a novel pre-step co-simulation approach for handling stiff system simulations based on formal subsystem transformations was proposed. The approach follows the idea of the Nearly Energy Preserving Coupling Element (NEPCE) scheme where exclusively subsystem inputs are modified for compensation of the co-simulation discretization error. This paper outlines a generalization of the presented pre-step co-simulation method for handling stiffness and direct feedthrough of subsystems. The generalized pre-step co-simulation algorithm is examined along a theoretical 2 DoF benchmark co-simulation example indicating outstanding co-simulation performance.

Paper Nr: 30
Title:

Feedback Linearization of Multilinear Time-invariant Systems using Tensor Decomposition Methods

Authors:

Kai Kruppa and Gerwald Lichtenberg

Abstract: Multilinear Time-Invariant (MTI) Systems can represent or approximate nonlinear systems behaviour in a tensor framework. The paper derives efficient algorithms for feedback linearization of MTI systems. Basic operations like products and partial derivatives of multilinear or higher order polynomials and Lie derivatives can be defined in terms of Canonical Polyadic (CP) tensors, as well as the parameters of MTI systems. The feedback linearizing controller design algorithm given in the paper results in a controller of a known fixed structure with predictable memory demand, which is a great advantage in case of implementation. The structure does not depend on the MTI plant and has to be adjusted to the application by setting its parameters only. Moreover, the MTI algorithm only involves numerical and no symbolic computations. This is relevant for large scale applications like heterogeneous networks e.g. for heat and power distribution, since the model can be represented by decomposed tensors to reduce the storage demand.

Paper Nr: 72
Title:

Measuring Perceptual Similarity of Syntactically Generated Pictures

Authors:

Nuru Jingili, Sigrid Ewert and Ian Sanders

Abstract: This paper shows how similar pictures can be generated using random and bag context picture grammars. An online survey was conducted to determine the similarity of the pictures generated by the picture grammars. Respondents were asked to rank pictures in order of similarity to the query picture. They were also asked to rank galleries of pictures from those containing pictures that are most similar to those containing pictures that are least similar. Furthermore, respondents were required to tell us how they determined the similarity of the pictures contained in the galleries. We then compared perceptual similarity with a chosen similarity measure — spatial color distribution descriptor (SpCD) — to determine if they are consistent. The spatial color distribution descriptor has provided excellent results in determining the similarity of computer-generated pictures, and so was seen as a good similarity measure for this research. The results show that there is a good correlation between the SpCD and perceptual similarity although in some instances humans do make different judgements.

Short Papers
Paper Nr: 52
Title:

Patient Pathway Workflow Model Identifying Overcrowding Indicators in Emergency Department

Authors:

Faten Ajmi, Sarah Ben Othman, Hayfa Zgaya Biau and Slim Hammadi

Abstract: The overcrowding situation in emergency department is serious problem worldwide. In fact, the majority of developing countries are interested in developing their hospital system in order to anticipate the overcrowding situations and ameliorate the quality of patient care. In this paper, we focus on patient pathway in an Adult Emergency Departments (AED). This process presents the main burden for overall system operation due to its growing dynamics and the distributed organizational structure of hospitals. In order to determine the key performance indicators for the internal functioning of AED, we are building a workflow model based on the real patient pathway to direct the patients into the dedicated service while respecting the quality of care according to the expectations and requirements of the patient. Our approach is tested on a set of real database from AED of CHRU in Lille (France). Simulation results show that the proposed model can determine 3 keys performances indicators to optimize in order to improve the patient pathway in the AED.

Posters
Paper Nr: 23
Title:

Algebraic Formal Modelling for EIGRP using ACP - Formal Description Modelling on EIGRP Routing Protocol

Authors:

Pedro Juan Roig, Salvador Alcaraz, Katja Gilly and Carlos Juiz

Abstract: Fast-converging routing protocols are necessary in order to keep up with the interconnected world we are living in and one of the quickest ones is EIGRP. In this paper, we are going to design two models for network devices running EIGRP by focusing on the main events happening on them. First, a non-timing model is going to be formally described, hence just studying the aforesaid main events without any time constraints. Then, a timing model is going to extend the former with the proper time values associated with each particular event. Both models are going to be formally described by means of manual algebraic derivations using Algebra of Communicating Processes (ACP).

Area 3 - Complex Systems Modeling and Simulation

Full Papers
Paper Nr: 11
Title:

Parameter Identification in Cyclic Voltammetry of Alkaline Methanol Oxidation

Authors:

Tanja Clees, Igor Nikitin, Lialia Nikitina, Sabine Pott, Ulrike Krewer and Theresa Haisch

Abstract: Alkaline methanol oxidation is an electrochemical process, perspective for the design of efficient high energy density fuel cells. The process involves a large number of elementary reactions, forming a complex reaction graph, and it is described by a system of non-linear differential equations of high order. The purpose of parameter identification is a reconstruction of reaction constants in this model on the basis of available experimental data. Cyclic voltammetry, a measurement of dynamical current-voltage characteristic of the cell, is especially suitable for analysis of electrochemical kinetics. In this paper we present several approaches for parameter identification in cyclic voltammetry of alkaline methanol oxidation. With the aid of global optimization methods and interactive parameter study we find four islands of solutions in parameter space, corresponding to different chemical mechanisms of the process. The main features of solutions are discussed and the reconstructed reaction constants are presented.

Paper Nr: 42
Title:

Development of a Perforated Diffusive Muffler for a Regenerative Blower

Authors:

Hyun Gwon Kil, Kwan Ho Jeon, Bo Youn Jang and Chan Lee

Abstract: A perforated diffusive muffler has been developed to reduce a high noise level that is generated from a regenerative blower. The noise consists of two components such as discrete frequency noise component at blade passing frequency due to rotating impellers and broadband noise component due to turbulence produced in the regenerative blower. Main contribution into the high noise level is due to the discrete frequency noise component. In order to effectively reduce the noise level of the regenerative blower, a perforated diffusive muffler has been designed and manufactured in this paper. Its experimental test showed that 23 dB of noise reduction has been achieved by attaching the muffler to the regenerative blower. Noise level of 85dBA generated by the regenerative blower was reduced to noise level of 62dBA.

Paper Nr: 77
Title:

Using Flexible Time Scale to Explore the Validity of Agent-based Models of Ecosystem Dynamics: Application to Simulation of a Wild Rodent Population in a Changing Agricultural Landscape

Authors:

Jean Le Fur and Moussa Sall

Abstract: Identifying parameters value is a major issue in model engineering. In discrete time agent-based models, time step is an important one as it determines the frequency at which agents realize their activity step. This parameter is commonly defined as a fixed constant during the model design stage. In particular cases, this may lead to biases as it may be sometimes difficult to determine if agents efficiently realize their activity step once each 1, 2 seconds, hour or the like. A simulation model of a rodent population has been used to study the effect of using a flexible time scale on its outcomes. Three types of processes have been considered as time dependent in the model, environment sensing, movement and life cycle (maturity, gestation...). A time step sensitivity analysis constitutes the principal result of this study. For the widest range of time step values, model’s behaviour is unrealistic and bound to algorithms artefacts. A very small range of time steps leads to simulation of a perennial rodents’ population. Biases bound to variable time step implementation are discussed. Using flexible time scale approach proved efficient to get insight into the model’s behaviour and fruitful clues to assess agents’ processes frequency in the actual ecosystem.

Short Papers
Paper Nr: 5
Title:

Internet of Things Meets BPM: A Conceptual Integration Framework

Authors:

Stefan Schönig, Lars Ackermann and Stefan Jablonski

Abstract: Business process management (BPM) is considered as a powerful technology to design, control, and improve processes. Recently, organizations have started contemplating the value that combining the inter-networking of all kinds of physical devices, i.e., the Internet of Things (IoT) with BPM could bring to an organization. BPM provides intelligent control over IoT devices by integrating and managing devices and data generated by them in business operations. Here, data from IoT devices needs to be analyzed and actions need to be taken based on that data. Since the real world as context of a BPM application changes drastically through the advent of IoT, it is worthwhile to investigate how the enactment of a BPM application changes or must be customized. In this paper, we first describe benefits and necessary adaptions w.r.t. the integration of IoT and BPM systems. Furthermore, we tackle two concrete adaption tasks, i.e., we introduce concepts for IoT enhanced process modeling as well as a technological integration architecture. Both approaches have successfully been evaluated in production industry.

Paper Nr: 14
Title:

Monte Carlo Simulation of Non-stationary Air Temperature Time-Series

Authors:

Nina Kargapolova

Abstract: Two numerical stochastic models of air temperature time-series are considered in this paper. The first model is constructed under the assumption that time-series are nonstationary. In the second model air temperature time-series are considered as a periodically correlated random processes. Data from real observations on weather stations was used for estimation of models’ parameters. On the basis of simulated trajectories, some statistical properties of rare meteorological events, like sharp temperature drops or long-term temperature decreases in summer, are studied.

Paper Nr: 31
Title:

Modeling Ethno-social Conflicts based on the Langevin Equation with the Introduction of the Control Function

Authors:

Alexandr Y. Petukhov, Alexey O. Malhanov, Vladimir M. Sandalov and Yury V. Petukhov

Abstract: In this article, we propose a model of ethno-social conflict based on diffusion equations with the introduction of the control function for such a conflict. Based on the classical concepts of ethno-social conflicts, we propose a characteristic parameter - social distance that determines the state of society from the point of view of the theory of conflict.A model based on the diffusion equation of Langevin is developed. The model is based on the idea that individuals interact in society through a communicative field - h. This field is induced by every person in a society, serves as a model of the information interaction between individuals. In addition, the control is introduced into the system through the dissipation function. A solution of the system of equations for a divergent diffusion type is given. Using the example of two interacting-conflicting ethnic groups of individuals, we have identified the characteristic patterns of ethno-social conflict in the social system and determined the effect the social distance in society has in development of similar processes with regard to the external influence, dissipation, and random factors. We have demonstrated how the phase portrait of the system qualitatively changes as the parameters of the control function of the ethno-social conflict change. Using the analysis data of the resulting phase portraits, we have concluded that it is possible to control a characteristic area of sustainability for a social system, within which it remains stable and does not become subject to ethno-social conflicts.

Paper Nr: 57
Title:

Improving the Characteristics of Two-Stage Fuel Pump by Optimizing the Blades Geometry

Authors:

Oleg Baturin, Daria Kolmakova, Grigorii Popov and Vasilii M. Zubanov

Abstract: The article presents a refining method for a two-stage screw centrifugal pump by the joint usage of optimization software IOSO, meshing complex NUMECA and CFD software ANSYS CFX. The pump main parameters: high-pressure stage rotor speed was 13300 rpm; low-pressure rotor speed was 3617 rpm by gearbox; inlet total pressure was 0.4 MPa; outlet mass flow was 132.6 kg/s at the nominal mode. This article describes the process of simplifying the calculation model for the optimization. The parameters of camber lines of the low-pressure impeller, transition duct, and high-pressure impeller blades for two sections (hub and shroud) were chosen as optimization parameters. The optimization goal was the increase of the pump efficiency with preservation or slight increase in the pressure head. The efficiency was increased by 3%.

Paper Nr: 60
Title:

Estimation of the Effect of 3D Grid Parameters on the Simulation of the Working Process of Axial Turbines

Authors:

Grigorii Popov, Valery Matveev, Oleg Baturin, Iuliia Novikova, Daria Kolmakova and Vasilii Zubanov

Abstract: This article describes the second part of the global work done by the authors aimed at finding the best settings for a numerical model for calculations of axial uncooled turbines using the RANS approach. The authors studied more than 80 papers published over the past 5 years in the examined field. Their analysis did not allow to identify unified recommendations for the creation of numerical models. The selection of model parameters is usually motivated by general considerations of numerical simulation, which follow from the method. In none of the papers the selection of parameters is correlated with the structure of the flow in the turbine. Many specific simulation issues were not covered at all. For the research, more than 1000 models of full-size axial turbines (including multistage turbines) and their elements were created. They differed in the number, size, parameters of the elements of finite volume meshes, in turbulence models, in the degree of simplification. The results were compared with the experimental data. As a result, the following was obtained: 1. A method for developing and optimizing the working process of turbines using numerical simulation based on the RANS approach is proposed. The search for the optimal turbine configuration is carried out using light computational models, which are based on the simplified channel geometry and the finite volume mesh. Their application makes it possible to reliably find the optimal turbine configuration 2.8 times faster. The characteristics of the selected variants are verified with the help of verification models that consider the real geometry of the channels and have a minimum error. 2. Recommendations are given on the selection of parameters for finite volume meshes and the selection of turbulence models for numerical models of the working process of axial turbines designed to perform optimization and verification calculations.

Posters
Paper Nr: 10
Title:

Universal Translation Algorithm for Formulation of Transport Network Problems

Authors:

Anton Baldin, Kläre Cassirer, Tanja Clees, Bernhard Klaassen, Igor Nikitin, Lialia Nikitina and Inna Torgovitskaia

Abstract: The formulation of transport network problems is represented as a translation between two domain specific languages: from a network description language, used by network simulation community, to a problem description language, understood by generic non-linear solvers. A universal algorithm for this translation is developed, an estimation of its computational complexity given, and an efficient application of the algorithm demonstrated on a number of realistic examples. Typically, for a large gas transport network with about 10K elements the translation and solution of non-linear system together require less than 1 sec on the common hardware. The translation procedure incorporates several preprocessing filters, in particular, topological cleaning filters, which accelerate the solution procedure by factor 8.

Paper Nr: 39
Title:

Simulation Coupling Limitations with Respect to Shared Entities Constraints

Authors:

Khadim Ndiaye, Flavien Balbo, Jean-Paul Jamont and Michel Occello

Abstract: Simulation coupling is a mean by which already developed tools are reused and run together for the sake of capitalizing on existing endeavours. A main challenge to microscopic simulation coupling is the synchronization of schedulers, which are in charge of ordering internal actions for their respective simulation. To achieve a consistent execution of the overall simulations, simulation coupling must tackle challenges to interoperability and schedulers’ synchronization. In the scope of microscopic simulations, functional coupling objectives can be categorized into different levels from coupled simulations that only exchange aggregated information, to a coupling that highlights novel behaviours. Our goal in this paper is to show that the existing coupling solutions fail to implement the problem where the coupling objective is to combine individual behaviors from diverse microscopic simulations, in order to create new ones. This failure is due to the fact that these solutions consider microscopic simulations to be coupled, as whole components with autonomous schedulers instead of a composite set of behaviors. The limitations are shown using the DEVS formalism to describe coupled microscopic simulation under different coupling objectives, with a formalization of constraints induced by shared components.

Paper Nr: 48
Title:

Temporal Causal Network Model for Appraisal Process in Emotion

Authors:

Fawad Taj and Michel C. A. Klein

Abstract: Most of the emotion theories consider appraisal as the major component in an emotional episode. The appraisal theories legitimately try to explain the actual process of appraisal. Number of computational architecture for emotional and cognitive agents exists, which try to incorporate the major cognitive appraisal theories, but they compromise on a certain aspect of the theories due to its complexity. In this paper, a temporal causal network model approach is used to address the dynamics and temporal processing of different evaluation checks in the appraisal component. The checks included in the model are inspired by the Component Process Model and other neuro and cognitive science literature. Simulations have been done to show the temporal causality between different evaluation checks.

Paper Nr: 58
Title:

Optimization of Nozzle Shape of Hydrogen-Oxygen Rocket Engine

Authors:

Valeriy Matveev, Vasilii Zubanov, Leonid Shabliy and Anastasia Korneeva

Abstract: The article presents a technique of parametric optimization of nozzle supercritical part of liquid-propellant rocket engine. Main approaches for parametric optimization were given. Two optimizers were mentioned. Thrust and specific impulse were chosen as optimization criteria. Simulation of chamber process was performed in ANSYS CFX with combustion model Eddy Dissipation. Two variants of combustion were considered: one global reaction and detailed chemical system with 8 components and 18 reactions. Comparison of results gives more smooth contours of parameters for set with detailed system against variant with one reaction for simulation of liquid-propellant rocket engine working with “hydrogen-oxygen” propellants. In result of optimization the nozzle length was shortened up to 15% virtually without thrust loss (0.18% reduction in thrust). Also the Pareto set in axis “thrust”-“nozzle length” was obtained.

Area 4 - Application Domains

Full Papers
Paper Nr: 6
Title:

Simulation-based Performance Analysis in Robotic Mobile Fulfilment Systems - Analyzing the Throughput of Different Layout Configurations

Authors:

Thomas Lienert, Tobias Staab, Christopher Ludwig and Johannes Fottner

Abstract: A robotic mobile fulfilment system for automated storage and retrieval of goods is investigated to determine reachable throughput as a function of the number of vehicles. The simulation model considers connected zones for manual order picking and replenishment of empty storage units. The results show a strong increase of blocking effects between vehicles if the number of vehicles within the system increases. This leads to a maximal throughput, which further vehicles cannot increase. We will show that changing the storage layout increases throughput. The results also show a linear correlation between the number of vehicles and the throughput for small numbers of vehicles. Here, analytical calculations are admissible since minor blocking effects do occur. However, the end of the linear correlation can only be found by simulation.

Paper Nr: 34
Title:

loop - A Trace-based Emulator for Vehicular Ad Hoc Networks

Authors:

Pedro Cirne, André Zúquete and Susana Sargento

Abstract: In this paper we present loop (loop over orderly phases), a trace-based emulator for Vehicular ad hoc networks (VANETs). This is an alternative and novel method to evaluate improvements on VANET protocols, which relies and takes advantage of real data samples collected from an existing network. Those samples are vehicles’ geographical locations and radio reception events, which represent mobility and communication patterns of the VANET. From those samples, loop creates a synthetic environment to simulate and evaluate communication protocols on the target VANET. loop also includes an interactive mode to manage the emulation process and a visualization mode that shows different time and geographical-dependent aspects. The development of loop was motivated by the need of an non-intrusive methodology to intensively analyse and deterministically compare the impact of several strategies for communication protocols and all their possible variations in a realistic scenario, both in terms of mobility and radio communication opportunities. Namely, we created loop to evaluate the impact of adding security features to the routing control plane of an VANET. Since the VANET includes hundreds of vehicles, the computational performance is critical to speed-up evaluations. With loop we were able to perform complex, multi-variable performance evaluations of 24 hour periods in durations ranging from 6 up to 30 minutes.

Paper Nr: 37
Title:

Modeling and Validation of a Complex Vehicle Dynamics Model for Real-time Applications

Authors:

Peter Riegl and Andreas Gaull

Abstract: This paper deals with the modeling and validation of a complex vehicle dynamics model implemented in Matlab, which should enable real-time simulation. In detail, the powertrain and the tire model Magic Formula by Pacejka are presented. In addition to the horizontal dynamics, which can also be found in single track models, the here presented vehicle model also takes into account the vertical motion as well as the pitch and roll behavior. Furthermore, the wheel load fluctuations during the driving maneuvers are included. The equations of motion are based on multi-body dynamics. Based on three driving scenarios, which are simulated in the software CarMaker, the quality of the driving dynamics model is evaluated.

Paper Nr: 38
Title:

Using Simulations for Exploring Interventions in Social Networks - Modeling Physical Activity Behaviour in Dutch School Classes

Authors:

Eric Fernandes de Mello Araújo, Bojan Simoski, Thabo van Woudenberg, Kirsten Bevelander, Crystal Smit, Laura Buijs, Michel Klein and Moniek Buijzen

Abstract: The reduction of childhood obesity through the promotion of a healthy lifestyle is one of the most important public health challenges at the moment. It is known that the unhealthy habits of children can cause unavoidable side effects in their early stage of life, including both physical and mental consequences. This work considers that the physical activity level of children is a behaviour that can be spread throughout the social relations of children in their daily life at school. Therefore, the aim of this work is to define what the best strategy is to find ’targets’ (i.e., influential children that can initiate behavioural change) for physical activity (PA) interventions that would affect the average PA of a population of Dutch school classes. We tuned a model based on the influence of the children’s peers in their social network, based on the data set from the MyMovez project – Phase I. Five intervention strategies were implemented, and their efficacy was compared. Once the targets were chosen, an increase of 17% was applied to their initial PA. Then, the diffusion model was run to verify the improvement on the PA of the whole network after one year. We discuss implications of the simulation results on which strategies may be used to make informed choices about the setup of social network interventions and future model improvements. Our results show that targeting more vulnerable children (i.e. in a worse environment) and applying a network optimization algorithm are the best solutions for this data set indicating that future interventions should aim for these two strategies.

Short Papers
Paper Nr: 51
Title:

Monte Carlo based Risk Analysis of Unmanned Aerial Vehicle Flights over Construction Job Sites

Authors:

Hashem Izadi Moud, Alireza Shojaei, Ian Flood and Xun Zhang

Abstract: While Unmanned Aerial Vehicles (UAVs) have been used on construction job sites for different purposes for over a decade, the risks and hazards of flying UAVs on construction job sites has not been either quantitatively or qualitatively assessed. Quantifying the risks of flying UAVs over general populations is a common practice in the general UAV industry. This study uses an established model that has been used to quantify the risks of flying UAVs over general population, propagates the bases of the model based on the construction industry needs, tailors some of the input of the model based on the construction industry specifications, and uses the Monte-Carlo Simulation method to quantify the risks of flying UAVs over a real construction job site adopted as a case study. This model is based on mishap rate for UAVs, population density of the area that UAVs fly over and the lethal area of UAVs that could be potentially fatal in the event of a crash. While this paper presents the very first effort in quantifying the risks of flying UAVs over construction sites, there is a need in the construction industry to tailor this model based on the needs of the industry to make the model more accurate.

Paper Nr: 70
Title:

Impact of Population Ageing on Hospital Demand

Authors:

Bożena Mielczarek and Jacek Zabawa

Abstract: This paper explores the consequences of demographic changes on future access to hospital beds. It is based on the situation in a Polish administrative region called the Wrocław Region (WR). The aim of the paper is to quantify the impact of population ageing on hospital demand with particular emphasis on neurological patients. A computer simulation model was used to project the population evolution during the period 2016-2030 and forecast the number of neurological patients to be admitted to the WR hospitals. We found that the growth of the WR population will have a large impact on the number of elderly patients, including persons with diagnosed neurological disorders. The simulation experiments predict a continuous rise in the demand, and the ageing alone will increase the number of neurological patients in WR, on average, by 8.5 % between 2016 and 2030.

Posters
Paper Nr: 12
Title:

Test Evaluation and Computational Modeling Applicability for Compression Moldability of Inert Explosive

Authors:

Jin Sung Lee and Jung Su Park

Abstract: Using an inert explosive powder, molding experiments were carried out. And a computational model analysis was performed to predict moldability behaviour of an inert explosive powder. In order to analysis the Shima-Oyane yield model to predict the behaviour of the densification for inert explosive powder, using an inert explosive powder was carried out moldability tests on the pressure, could be obtained volumetric strain on the pressure, relative density and so on. Based on the results of the curve fitting, it could be derived the parameters for the yield function of the cap with the critical state. Finite element analysis for both double action pressing and isostatic pressing process of the two yield models were performed. And changes in relative density and densification behaviour of an inert explosive powder were analysed. In addition, it investigated the distribution of the relative density or volumetric strain caused by the overall and local variations. It was founded the maximum stress and position etc. under working pressure of inert explosive powder.

Paper Nr: 20
Title:

Knowledge Discovery for Interactive Dialogue Management with Geoinformation Service

Authors:

Stanislav Belyakov, Alexandr Bozhenyuk, Marina Belyakova and Sergey Zubkov

Abstract: The problem of adaptation of the geoinformation service to the increasing amount of knowledge and modification of the spatial database structure is analyzed in this article. The necessity to take into account the factors of changes in information basis is considered by a visualization of searching procedure and by analyzing spatial data of the geoinformation service. The paper proposes a method for solving the problem, based on the principle of the evolution of technical systems. In this problem the evolutionary principle considers the continuous rules generation procedure by the geoinformation service containing knowledge of useful cartographic objects for visual analysis. The rules are considered as hypotheses that require collective confirmation from the clients of the service. Confirmation of any rule is a selection of useful knowledge for further implementation. Thus, the proposed mechanism provides a continuous adaptation to a changing information environment through the development and rule selection. The mechanism of generation is analyzed and the structure of rules is determined. The mechanism of collective confirmation of rules is considered as well.

Paper Nr: 44
Title:

Semi-Autonomous Navigation for Virtual Tactical Simulations in the Military Domain

Authors:

Juliana R. Brondani, Luis A. L. Silva, Mateus B. Rutzig, Cesar T. Pozzer, Raul C. Nunes, João B. Martins and Edison P. de Freitas

Abstract: Integrated constructive and virtual simulations are becoming popular for tactical training in the military domain. An important aspect concerning the integration of these simulation models in the construction of virtual tactical simulations is the modelling and implementation of different kinds of semi-autonomous agents. A fundamental feature of these agents is the capability of intelligently and realistically modelling task-oriented navigation activities in large virtual terrain simulation environments, while following underlying military doctrine and tactics. This paper reviews important navigation issues that emerge in such simulation systems and prominent Artificial Intelligence (AI) techniques that have been explored to solve them. From this analysis, a hybrid, semi-autonomous navigation framework is proposed aiming to fulfil the needs of virtual tactical training simulations, more specifically, in the military domain. As implemented in a system for the virtual tactical simulation of artillery battery tasks, the framework shows how to overcome the challenges of implementing realistic global and local navigation behaviours for military units and, at the same time, it shows that the semi-autonomous behaviours implemented are of primary importance to allow interaction with users for learning purposes in the simulation exercises.

Paper Nr: 74
Title:

A Stochastic Approach for Damage Modelling of Cast Alloys

Authors:

Christian Mühlstätter

Abstract: The increasing interest of cast Aluminium alloys in structural application asks for appropriate simulation approaches. Besides the constitutive behaviour, damage properties play an important role for this material. The damage behaviour is significantly influenced by the microstructure. Due to the specific morphology of cast microstructure and the random spatial deviation of voids, a novel concept of material modelling is necessary. In this study, a concept for stochastic material characterisation and modelling in structural Finite Element simulations is introduced. Therefore, a test matrix for experimental tests is discussed. Based on the generated experimental data a stochastic evaluation is performed by a goodness-of-fit test. The achieved characterisation knowledge is used to introduce the concept for stochastic material modelling of Aluminium cast alloys.